Method and apparatus for lining a pipe

Abstract

The method for rehabilitating a damaged section of a pipe without a need for a resin absorbent liner is provided. The method includes pumping a low viscosity material towards a damaged section of pipe and changing the viscosity prior to dispensing of the material. For example, the material may be partially cured prior to dispensing. The partially cured or higher viscosity material is compressed between an inflating bladder and interior wall of the pipe, and the material that is allowed to fully cure. The bladder either can then be removed from the pipe or could be allowed to maintain in the pipe providing a new interior surface for the repaired pipe.

What is claimed is: 
     
       1. A method of rehabilitating a damaged section of a pipe that obviates the need for a resin absorbent liner, comprising:
 positioning a bladder in a pipe; 
 dispensing a material capable of curing and hardening between an exterior surface of the bladder and the interior surface of the pipe; 
 wherein the material capable of curing and hardening is at least partially cured prior to being dispensed; 
 compressing the at least partially cured material between the bladder and the pipe; and 
 allowing the material to continue to cure; 
 wherein the material capable of curing and hardening is a one-part, UV cured resin; 
 pumping the UV-cured resin through a light tunnel to at least partially cure the resin prior to dispensing. 
 
     
     
       2. The method of  claim 1  further comprising removing the bladder from the pipe after the material has cured. 
     
     
       3. The method of  claim 1  wherein the step of at least partially curing the resin increases the viscosity of the pumped resin. 
     
     
       4. The method of  claim 1  further comprising inflating the bladder in the pipe to compress the material between the bladder and the pipe. 
     
     
       5. The method of  claim 4  wherein the step of positioning the bladder in the pipe comprises inverting the bladder through the pipe. 
     
     
       6. The method of  claim 5  wherein the material is dispensed rearward of the inverting face of the bladder between an exterior surface of the bladder and the damaged section of pipe. 
     
     
       7. The method of  claim 6  wherein the material is pumped from ahead of the inverting face of the bladder and toward the inverting face of the bladder. 
     
     
       8. A method of rehabilitating a damaged section of a pipe that obviates the need for a resin absorbent liner, comprising:
 positioning a bladder in a pipe; 
 pumping a material capable of curing and hardening, and having a first viscosity within the pipe; 
 changing the viscosity of the material being pumped in the pipe; 
 dispensing the material comprising the changed viscosity between an exterior surface of the bladder and the pipe; 
 compressing the material between the bladder and the pipe; and 
 allowing the material to cure; 
 wherein the change in viscosity comprises raising the viscosity of the material; 
 wherein the material is a one-part, UV-cured resin; 
 wherein the step of changing the viscosity of the material comprises pumping the resin at least partially through a UV light source. 
 
     
     
       9. The method of  claim 8  wherein the material is a two-part resin. 
     
     
       10. The method of  claim 9  wherein the step of changing the viscosity of the material comprises mixing the two parts of the resin just prior to dispensing the resin. 
     
     
       11. The method of  claim 8  further comprising removing the bladder from the pipe. 
     
     
       12. The method of  claim 8  wherein the bladder remains in the pipe after the material has cured and hardened. 
     
     
       13. A method of dispensing a material a distance in a delivery apparatus having a starting end and a dispensing end, comprising:
 pumping a material capable of changing viscosities through the delivery apparatus; 
 at least partially increasing the viscosity of the material while pumping the material and near the dispensing end of the delivery apparatus; 
 wherein the increase in viscosity is controlled; and 
 dispensing the material comprising the at least partially changed viscosity out of the dispensing end of the delivery apparatus; 
 wherein the material is a UV-cured material, and the step of at least partially changing the viscosity comprises pumping the material adjacent a light source. 
 
     
     
       14. The method of  claim 13  wherein the light source comprises a light tunnel including a plurality of light initiators. 
     
     
       15. A method of rehabilitating a section of a pipeline, comprising:
 pumping a material capable of curing through a delivery hose, said material having a viscosity of less than 10,000 cP; 
 using light or heat to change the viscosity of the material to 10,000 cP or greater; and 
 applying the material comprising the changed viscosity to the interior of the pipeline. 
 
     
     
       16. A method of rehabilitating a damaged section of a pipe that obviates the need for a resin absorbent liner, comprising:
 dispensing a one-part material capable of curing and hardening to the interior surface of the pipe; 
 wherein the material capable of curing and hardening is at least partially cured prior to being dispensed; and 
 allowing the material to continue to cure. 
 
     
     
       17. A method of rehabilitating a damaged section of a pipe that obviates the need for a resin absorbent liner, comprising:
 positioning a bladder in a pipe; 
 pumping a one-part material capable of changing viscosities through a delivery apparatus having a dispensing end; 
 at least partially increasing the viscosity of the one-part material while pumping the material and near the dispensing end of the delivery apparatus; and 
 dispensing the one-part material comprising the at least partially changed viscosity out of the dispensing end of the delivery apparatus and between an exterior surface of the bladder and an interior surface of the pipe. 
 
     
     
       18. The method of  claim 17  wherein the viscosity is increased using light. 
     
     
       19. The method of  claim 17  wherein the viscosity is increased using heat.